Weatherwatch: When migrating cranes fly high good weather is likely

Several of the world's 15 species of cranes migrate vast distances, arriving in their winter homes just as autumn is at its height. Like geese, their early arrival is supposed to foretell a cold winter, though it is in reality a reflection of current, rather than future, weather conditions. Cranes are vocal birds, and when they are calling loudly, folklore predicts bad weather, and the birds are said to be consulting with one another over which course of action to take to avoid the coming storm.

Conversely, when migrating cranes fly high, straight and true, folklore says that good weather is likely. And certainly flocks of birds such as cranes are more likely to travel when weather conditions are favourable, with the passing of a cold front bringing clear weather and a following wind. This applies to the common crane of Europe and Asia, and also to the whooping crane – North America's tallest bird, and at one time, with just two dozen individuals, the rarest. Whooping cranes usually migrate when high pressure has brought clear skies, and either no wind or a light tailwind. When low pressure dominates, they will come to ground and wait days, if necessary, before continuing their journey.

One species, the demoiselle crane, doesn't always have a choice. These delicate birds undertake one of the most perilous journeys of all, over the Himalayas, reaching altitudes of up to 8,000 metres as they fly through snowstorms to safety on the other side.